Any way that I can securely wipe free internal storage on Android? I am not talking about secure deleting, but just wiping whatever is possible to recover.

2 Answers 2


The most reliable method is to manually copy large non-sensitive files (such as Linux images or the LibreOffice Installer Setup File) to the partition that you wish to erase the free space from, delete and repeat it around THREE to FIVE times. Ensure the files you copy fill up the drive as much as possible, i.e. start copying small files when the large ones are too big to fit in the last remaining MB / KB of free space.

If you don't want to mess around finding files to write, you can use a utility called Dummy File Creator: http://www.mynikko.com/dummy/

This will allow you to create files of a specific size containing random data (ensure the Random File Content option is selected).

  • 1
    I quite like this. might try it.
    – Dan Brown
    Commented Nov 11, 2016 at 9:48

There are several apps claiming to help you out with this, see my Secure Wipe app list. They support different sub-sets of actions (e.g. only wiping free space versus "secure deleting files", or only working on SD card) – so make sure to read their descriptions. Secure Eraser might work for your case.

  • Nice and detailed list. I tried Secure Erase with iShredder 3 and Secure Eraser. It eliminates most of data, but still a lot of files are recoverable. I am using DiskDigger Pro to recover files.
    – Pablo
    Commented Jan 10, 2016 at 20:56
  • That's surprising, and not good news. Bad enough if it happens with one of those apps, but two? Did you try some of the others, e.g. Andro Shredder or Disk Sanitizer as well?
    – Izzy
    Commented Jan 10, 2016 at 21:36
  • The result is same. About 1600 files are very well recoverable. However, initially there were about 22000 files.
    – Pablo
    Commented Jan 11, 2016 at 12:24
  • OK, so it's "better than nothing" – but far from "working as expected". All those apps claim to securely wipe all free space, which they obviously don't manage. Maybe too much space? Tried running them multiple times? Not that I think that will make a difference (unless "free space to wipe" is selected "in random order"). Thanks for testing!
    – Izzy
    Commented Jan 11, 2016 at 12:37
  • 1
    Yes, I have run them multiple times. Many of those 1600 files(mostly pictures) are partially damaged, but still can be recognizable. They are from deleted gallery items. One strange thing I noticed - none of applications produced low memory warning on device, which makes me think that the file they create to wipe data is not exactly as much big as free space. Unless app can suppress low memory warning. Internal memory(which is only thing my phone has) is consisting of 32GB. Free space is 6GB.
    – Pablo
    Commented Jan 11, 2016 at 13:59

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .